No, you can't send it back to them. Oddly enough, the return address won't actually be related to the vendor...
If they sent you some random strain that you didn't order, and don't respond to queries, then raise a dispute when you can. This seems to be happening more and more. Who thinks it's reasonable to send a different strain when that's not what's been ordered?! Sort it out. It's completely unacceptable, and I'd dispute too.
If they sent you some random strain that you didn't order, and don't respond to queries, then raise a dispute when you can. This seems to be happening more and more. Who thinks it's reasonable to send a different strain when that's not what's been ordered?! Sort it out. It's completely unacceptable, and I'd dispute too.

